DFT calculations and in situ DRIFTS study of CO oxidation on CeO2/Co3O4 catalyst

The surface structures, CO adsorption, and oxidation-reaction properties of CeO2/Co3O4(110) have been investigated by using density functional theory including on-site Coulomb corrections (DFT+U) and in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS). Results indicate that CO can be chemisorbed on the Co sites of the terrace and interface of CeO2/Co3O4(110). At the interface, adsorbed and gas-phase CO reacting with lattice oxygen are investigated, respectively. It has been found that the lattice oxygen at the interface is more likely to be attacked by gas-phase CO directly to form adsorbed CO2. For desorption of the CO2, very high energy barriers are required. Furthermore, the infrared spectra reveal that the intermediate species at interface still exist even at 300 °C.